i have a giant breed pup, newfoundland and i was told by a cpuole of his vets that he should take glucosamine chondroitin for his joints. he also takes nuvet plus for his skin and coat.other than those issues the food should provide all that he needs.the glucosamine chondroitin goes by the dogs weight so its best to ask the vet about the dose. my boy takes 3 a day.